Combined spray drier



Now 25, 1930. s. HECHENBLEIKVNER 1,732,822

COMBINED SPRAY DRIER AND un'lmn Filed may 1a, 19?

` BY 21 y AT RNEYS l v Patented Nov. 25,1930

d, A UNITED STATES PATENT OFFICE INGENUIN HECHENBLEIKNER, OF CHARLOTTE,NORTH CAROLINA, ASSIG-NOR, BY MSN'E ASSIGNMENTS, TO CHEMICALCONSTRUCTION CORPORATION, A CORPORATION OF DELAWARE COMBINED SPRAYDRIER-AND BURNER Application led May 18, 1927. Serial No. 192,463.

This invention relates to a spray drying apparatus, and moreparticularly to a combined spray drier and burner.

Heretofore it has been the common practice 5 in the art to place a sprayforming device l centrally of a large drying chamber and preferably nearthe ceiling wall of said chamber, the spray forming apparatusbeingoperated to forml a mist or a spray which substantially The ceiling wallof the chamber is provided with passages or openings through which hotgases are introduced into the chamber to dry the spray or mist formedwithin the chamber. It has been the ractice hitherto to heat the dryinggases in urnaces or other heating apparatus at points removed'from thedrying chamber and to conduct the hot gases from said furnace to thedrying chamber. This is always accompanied by large heat losses and inaddition thereto it .necessitates av plurality of installationsoccupying considerable space. It is the object of the present inventionto provide a unitary apparatus which is compact in construction andsimple in operation to accomplish both the heating of the gases and thedrying of the spray with the resulting elimination of the greaterportion of the heat losses and resulting in a greater eiciency ofoperation of the entire system.

These objects are accomplished by rovid'- ing an enclosure which ispartitions into a 'combustion chamber' and a drying chamber, thepartition being made of fire brick and being provided with a largenumber of passages to permit the passage of the `hot gases formed in thecombustion chamber intov the drying chamber.

In the drawings, Fig. 1 is a sectional view of yan installationembodying the present invention, Fig. 2 is a side view of saidinstallation,

Fig. 3 is a top view of the apparatus, and Fig. 4 is a sectional view ofa modified form of the apparatus.

Referring to Fig. 1, 10 represents a large cylindrical enclosure made ofheat resisting .material and provided with an opening 11 in the bottomthereof. 12 is a. rotating scraper which serves to feed the dry `powderformed fills at least the upper half of the chamber.v

in the drying chamber to the screw conveyor 13.

The enclosure 10 is provided with an arched ceiling 14 made of firebrick and is additionally provided with a partition 15 also made of firebrick which is disposed a short distance below the ceiling 14. Thepartition 15 thus divides the enclosure 10 into a dryin cham-i ber 16and a combustion chamber 1 The cylindrical casing 18 is mountedcentrally of the walls 14 and 15 and projects into.- the 'drying chamber16 and is insulated from the combustion chamber by means of the layersof heat insulating material 19. The spraying device 20 which is operatedby the motor' 21 is supported within the casing 18. The pipe 22 feedsthe liquid to the spraying device 20.A The casing 18 is open at its topand forms a cold air inlet for the spraying apparatus which passesthrough the gas heating chamber or combustion chamber. This casing 18 isheat insulated from the combustion chamber by the aforesaid heatinsulating material 19. With this construction cold air may be drawninto the spray head and this is utilizable for 'purposes as describedAby me in my copending application Serial No. 192,464 filed of even ldateherewith. A A platform 23 surroundsthe enclosure 1'0 at approximatelythe level of the partitioning wall 15 and supports a plurality 0f fuelburners 24 which enter the apertures 25 in the outer wall of thecombustion chamber 17. The platform 23 also supports the distributingpipe 26 which substantially surrounds the enclosure 10 and is connectedto any source of fuel supply which may be of any nature but ispreferably a generators. The short vertical conduits 27 serve to connectthe fuel distributing conduit 26 with each of the fuel thereto. d

The air conduit 28 is disposed over the top of the enclosure 10 and hasconnected thereto air feed pipes 29 which serve to lfeed air from 28 isalso connected by means of a plurality of conduits 31 to openings 41 inthe ceiling gaseous .fuel obtained from gasburners 24 and supply` K wall14 of the combustion chamber to supply cold air thereto which is to beheated by the heat of combustion. A blower 32 serves to maintain apredetermined pressure of air in the conduit 28 so as to maintain thenecessary flow of air through the feed pipes 29v for the burners as Wellas to maintain a suithe drying chamber 16 to dry the spray formedtherein and to cause the precipitation of the dry powder.

In addition to the heat resisting material which constitutes the wall ofthe enclosure 10, the outer wall of the combustion chamber 17 isadditionally provided with another layer of heat resisting material 34.

In operation, the blower 32 maintains a predetermined pressure of air inthe conduit 28 and causes the distribution of that air through theburners 24 to support combustion of the fuel that enters said burners byway of the fuel distributing conduit 26 and also serves to supply thenecessary amount of air which enters the combustion chamber 17 by way ofthe conduits 31. The hot air as well as the combustion products passinto the drying chamber 16 by way of the passages 33 and perform thefunction of vaporizing and drying the fine spray or mist and causing theprecipitation of a dry, finely divided powder which is carried out bymeans of the scraper 12 and the screw conveyor 13. y

If desired, instead of causing the apparatus to be operated undersuper-atmospheric pressure, the apparatus may be operated by suction, asshown in Fig. 4. Under these conditions the air conduit 28 is eliminatedand a suction blower 40 is connected at a point near the bottom of thedrying chamber 16 which serves to draw air from this atmospheresurrounding the enclosure 10 through the burners 24 as well as throughthe openings 41 in the ceiling wall 14 of the combustion chamber.

A number of advantages result from the apparatus above described, amongwhich may be mentioned the following:

1. By means of the apparatus described herein, a very uniformdistribution of the hot air and gas mixture thoroughout the dryingchamber is obtained which leads to a higher drying capacity for achamber of given size and to a higher heat eiiciency of the entireapparatus. v

2. An installation designed in acordance with the embodiment of theinvention disclosed herein results in a saving of the originalinstallation and in a saving of space occupied by the installation.

3. The heat losses are reduced to a minimum and the operation costs ofthe apparatus are substantially reduced.

4. The construction is simple and the cost of repairs is therebyreduced.

It will also be apparent that While I have shown and described myinvention in the preferred form, many changes and modifications may bemade in the structure disclosed without departing from the splrit of theinvention, delinedvin the following claims.

I claim: i

1. A combined spray drying and gas combustion apparatus built into aunitary structure comprising a spray drying chamber having an aperturedupper wall, and a combustion chamber disposed immediately thereover forgenerating and supplying hot gases to said drying chamber through saidapertured upper wall.

2. A combined spray drying and gas combustion apparatus built into aunitary structure comprising a spray drying chamber having an aperturedupper wall, a combustion chamber disposed immediately thereover forenerating and supplying hot gases to said rying chamber through saidapertured upper wall, and a spraying apparatus disposed centrally ofsaid wall and projecting into said drying chamber.

3. A combined spray drying and gas combustion apparatus built into aunitary structure comprising a spray drying chamber having an aperturedupper wall, and a combustion chamber disposed immediately thereover forsupplying hot gases to said drying chamber through said apertured upperwall, said combustion chamber being provided with gas inlets, and a coldair inlet for said spraylng apparatus passing through said combustionchamber.

4. A combined spray drying and gas combustion apparatus built into aunitary structure comprising a spray chamber having an apertured upperwall, a casing mounted centrally of said wall, a spraying apparatusmounted in said casing and projecting into the spray chamber, and anannular combustion chamber surrounding said casing for generating hotgases and for supplying the same to said spray chamber through saidapertured wall.

5. A combined spra drying and gas combust-ion apparatus bui t into aunitary structure comprising. a spray drying chamber having an upperwall having a plurality of apertures distributed over a large areathereof, an air heating chamber disposed immediately thereover forgenerating hot ases and supplying the same to said drying c amber, and aspraying apparatus disposed centrally of said wall and pro'ecting intosaid drying chamber through sai apertured wall.

6. A comb-ined spra drying and gas combustion apparatus ui t into aunita structure comprising a spray drying cham r having an' aperturedupper wall, an annular gas heatin chamber disposed immediatelythereoveror supplying hot gas to said dry-l ingchamber, said gas heatingchamber being lprovided with gas inlets, and a cold air inlet for said sraying apparatus passing centrally throng said annular gas heatingchamber. Y 7. A combined spra drying and gas comu -bustion apparatus buit into a unitary structure comprlslng a spray chamber having an upperwall having a plurality of a rtures distributed over a large area thereoa casing mounted centrally of said'wall, a spraying apparatus mounted insaid casing and projecting into the spray chamber, and an annulargasproducing chamber surrounding said casing to supply hot gas to saidspra chamber through said apertured u per wal lzo 8. A combined s radrying an gas combustion apparatus ui t into a unitary structurecomprising a fuel supply pipe, an air supply ipe, a combustion chamber,aburner dispose 1n said combustion chamber, means for supplying fuel andair under ressure to said burner, a spray drying cham r, a wall havingpassages thereinpermitting the hot gases to pass from said"combustionchamber t'o said spray chamber disposed between@ said i A chambers, anda spray 'drier located at said chamber.

9. A combined spra drying and gas combustion apparatus bu` t into aunitary strucwall and extending into said spray drying I 35, turecomprising an enclosure, a wall separating said enclosure into acombustion chamber v and a drying chamber, said wall havin a pluralityof passages therein burners ',sposed in said vcombustion chamber, meansfor o supplying air and-fuel under pressure to said burners, and a spraydrier located at said wall and extending into said spray drying chamber.

Signed at Charlotte, in the county of Mecklenburg and State of NorthCarolina,

this 16th dav of MaHyA. D. 1927. A INGENUIN CHENBLEIKNER.

